From: Ian Rogers <irogers@google.com>
Date: Mon, 4 May 2026 08:12:22 +0000 (-0700)
Subject: perf libdw: Fix callchain parent update in ORDER_CALLER mode
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0e18b5bb7c9d2b4c6295c5307658759fdc280e39;p=thirdparty%2Fkernel%2Fstable.git

perf libdw: Fix callchain parent update in ORDER_CALLER mode

Fix the parent srcline lookup in `libdw_a2l_cb()` to target the
correct parent node depending on the callchain order
(ORDER_CALLER/ORDER_CALLEE).

This ensures inline callchains are not corrupted when nest depth > 2.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zecheng Li <zli94@ncsu.edu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---

diff --git a/tools/perf/util/libdw.c b/tools/perf/util/libdw.c
index 216977884103..301642084c69 100644
--- a/tools/perf/util/libdw.c
+++ b/tools/perf/util/libdw.c
@@ -4,6 +4,7 @@
 #include "srcline.h"
 #include "symbol.h"
 #include "dwarf-aux.h"
+#include "callchain.h"
 #include <fcntl.h>
 #include <unistd.h>
 #include <elfutils/libdwfl.h>
@@ -80,7 +81,6 @@ static int libdw_a2l_cb(Dwarf_Die *die, void *_args)
 	struct symbol *inline_sym = new_inline_sym(args->dso, args->sym, dwarf_diename(die));
 	const char *call_fname = die_get_call_file(die);
 	char *call_srcline = srcline__unknown;
-	struct inline_list *ilist;
 
 	if (!inline_sym)
 		return -ENOMEM;
@@ -89,14 +89,20 @@ static int libdw_a2l_cb(Dwarf_Die *die, void *_args)
 	if (call_fname)
 		call_srcline = srcline_from_fileline(call_fname, die_get_call_lineno(die));
 
-	list_for_each_entry(ilist, &args->node->val, list) {
-		if (args->leaf_srcline == ilist->srcline)
+	if (!list_empty(&args->node->val)) {
+		struct inline_list *parent;
+
+		if (callchain_param.order == ORDER_CALLEE)
+			parent = list_first_entry(&args->node->val, struct inline_list, list);
+		else
+			parent = list_last_entry(&args->node->val, struct inline_list, list);
+
+		if (args->leaf_srcline == parent->srcline)
 			args->leaf_srcline_used = false;
-		else if (ilist->srcline != srcline__unknown)
-			free(ilist->srcline);
-		ilist->srcline =  call_srcline;
+		else if (parent->srcline != srcline__unknown)
+			free(parent->srcline);
+		parent->srcline = call_srcline;
 		call_srcline = NULL;
-		break;
 	}
 	if (call_srcline && call_srcline != srcline__unknown)
 		free(call_srcline);